Appendicitis

  1. Core 1 (Pre-Clerkship)
    • Biomedical Science
      • Anatomy and Imaging
        • The Alimentary Tract and GI Circulation
      • POCUS
  2. Core 2 (Clerkship)
    • Pediatric Emergency Medicine Optional Reading - CDEM Approach to Pediatric Abdominal Pain
  3. Core 3 (Post Clerkship) Electives that may further knowledge - Peds EM

History

  • Loss of appetite 
  • Abdominal pain – can be periumbilical in early stages, but typically located in the right lower quadrant
  • Vomiting – usually after the onset of pain
  • Fever – usually 24-48 hours after symptom onset
  • Diarrhea
  • Lethargy/irritability 

Physical Exam Findings of Acute Appendicitis 

Exam Finding 

Description 

Significant Pain with Movement 

Severe pain elicited by cough, hopping, or when the examiner bumps the exam table or soles of the patient’s feet 

Involuntary Muscle Guarding 

Reflex tightening of the abdominal muscles during palpation 

Rebound Tenderness 

Pain increases when steady pressure applied to the RLQ for 10–15 seconds is suddenly released 

Percussion Tenderness 

Pain elicited by gentle tapping or percussion over a tender area, suggesting peritonitis 

McBurney’s Point Tenderness 

Localized tenderness with some rigidity at a point one-third the distance from the anterior superior iliac spine to the umbilicus; most reliable sign of appendicitis 

Rovsing's Sign 

Pain in RLQ when palpating the left lower quadrant, sign of peritonitis 

Obturator Sign 

Pain on flexion and internal rotation of the right hip, indicating irritation of the obturator internus muscle due to a pelvic appendix 

Iliopsoas Sign 

Pain on extension of the right hip, indicating retrocecal appendicitis 

Infographic showing physical exam signs for appendicitis: McBurney point tenderness, Rovsing sign, Psoas sign, and Obturator sign.

Source: Rapid Review: Appendicitis - RoshReview.com 

The image illustrates four classic appendicitis exam findings. McBurney point tenderness is located two-thirds of the way from the umbilicus to the ASIS; Rovsing sign is pain in the right lower quadrant when palpating the left lower quadrant; the Psoas sign shows pain with hip extension; and the Obturator sign elicits pain with flexion of the knee and internal rotation of the hip. Each diagram shows the relevant anatomy and maneuver to help identify appendiceal irritation.

Risk stratify for appendicitis based on symptoms and labs: Pediatric Risk Calculator or CHOP pathway definitions 

Source: CHOP appendicitis pathway 

Evaluation

  • Consider laboratory workup for further evaluation in equivocal cases
    • CBC, BMP, CRP, UA, pregnancy
    • Other workup is dependent on other differential diagnoses
  • Imaging for diagnosis in high probability cases
    • RLQ Ultrasound – First Line
    • MR Appendix
      • First line if weight >100kg due to difficulty visualizing appendix on ultrasound with larger body habitus
      • Second line if secondary signs of appendicitis on US, but appendix is not seen 

Management of appendicitis 

  • NPO + IVF as clinically indicated
  • Surgical consultation for appendectomy
    • Antibiotics in cases of perforation and post-operative abscess – typically ceftriaxone and metronidazole
      • For post-operative abscess, 7-day course of antibiotics (discharge on oral ciprofloxacin and metronidazole)
    • For cases of perforated appendicitis with abscess
      • Delay appendectomy
      • Consider drainage by interventional radiology + 14 day course of antibiotics
      • Interval appendectomy in 4-6 weeks 

  • Symptoms of appendicitis may be non-specific in younger children and pain may not be located in the right lower quadrant 
  • Specific exam maneuvers such as McBurney’s point, Rovsing sign, Psoas sign, and Obturator sign may help to assess for appendicitis 
  • Ultrasound is usually the first line diagnostic test followed by MRI if non-diagnostic 
  • Most common causes include fecalith, undigested food, or foreign material 
    • Less common causes include enteric pathogens that can cause lymphoid hyperplasia with obstruction - Adenovirus, measles, EBV 
  • Most common in age 11-20 years old 
  • Higher rate of perforation on presentation in younger children likely due to non-specific symptoms in younger children 

Click the drop down to reveal the correct answers

Q1: What is the most common age range for appendicitis?

Q2: What is the most reliable physical exam finding for appendicitis?

Q3: A patient has RLQ pain when the left lower quadrant is palpated. What is this sign called and what does it suggest?

Q4: Why is appendicitis often missed in children under 5 years old, and what is a potential consequence?

Q5: A child has RLQ pain worsened by hip extension. What is this sign and what does it suggest?

Q6: When is MRI preferred over ultrasound for diagnosing appendicitis?

Q7: What imaging modality is first-line for suspected appendicitis in pediatric patients?

Q8: In a post-pubertal female with abdominal pain, what conditions must be ruled out before diagnosing appendicitis?

Q9: What antibiotics are typically used for perforated appendicitis?

Answers

Q1: 11–20 years old

Q2: Answer: McBurney’s point tenderness — located one-third the distance from the anterior superior iliac spine to the umbilicus.

Q3: Rovsing’s sign, suggesting peritoneal irritation due to appendicitis.

Q4: Symptoms may be non-specific or atypical, leading to delayed diagnosis and higher perforation rates (up to 100%).

Q5: Iliopsoas sign, suggesting a retrocecal appendix irritating the psoas muscle.

Q6: If the appendix is not visualized or in patients >100 kg with equivocal ultrasound findings. MRI provides better visualization in patients with higher body habitus or unclear US results.

Q7: Right lower quadrant abdominal ultrasound. 

Q8: Ectopic pregnancy and ovarian torsion — check urine pregnancy test and consider pelvic ultrasound with Doppler.

Q9: Ceftriaxone and metronidazole.